Rotary stepping solenoid

ABSTRACT

A rotary stepping solenoid having a hinged armature and converter means between the armature and the solenoid output shaft for converting arcuate moment of the armature to rotary movement of the output shaft. This rotary stepping solenoid is similar in operation and construction to known rotary solenoids of the hinged armature type except for the additional structure of: 1 A PLURALITY OF BALL RACE CAMS IN AN UPPER SURFACE OF THE OUTPUT SHAFT, 2 THE ARMATURE BEING SPRING BIASED INTO ITS UPPER DE-ENERGIZED POSITION, 3 DETENT MEANS FOR HOLDING THE OUTPUT SHAFT IN THE POSITION TO WHICH IT HAS BEEN MOVED, AND 4 A SPRING ARM FOR MOVING THE CONVERTER BALL UP INTO THE ARMATURE CAM AND OUT OF CONTACT WITH THE SHAFT CAM BUT IN OPERATIVE POSITION WITH RESPECT TO THE NEXT SUCCEEDING CAM IN THE UPPER SURFACE OF THE OUTPUT SHAFT.

United States Patent Ganowsky 51 Sept. 19, 1972 [S4] ROTARY STEPPING SOLENOID [72] Inventor: Raymond J. Ganowsky, Clifton Springs, N.Y.

[73] Assignee: Cllltronics, lnc., Clifton Springs,

[22] Filed: Nov. 27, 1970 [21] Appl.No.: 93,360

[52] US. Cl. ..335/228, 310/37, 74/99 [51] Int. Cl. ..H01f 7/08 [58] Field of Search ..335/228, 272, 274, 276; 310/20, 21, 23, 37; 74/89, 99

[56] References Cited UNITED STATES PATENTS 3,419,831 12/1968 Ganowsky ..335/228 3,435,391 3/1969 Straub ..335/228 3,505,629 4/1970 Krautwald et al ..335/276 X Primary Examiner-George Harris Attorney-Schovee & Boston [57] ABSTRACT A rotary stepping solenoid having a hinged armature and converter means between the armature and the solenoid output shaft for converting arcuate moment of the armature to rotary movement of the output shaft. This rotary stepping solenoid is similar in opera tion and construction to known rotary solenoids of the hinged armature type except for the additional structure of:

1 a plurality of ball race cams in an upper surface of the output shaft,

2 the armature being spring biased into its upper deenergized position,

3 detent means for holding the output shaft in the position to which it has been moved, and

4 a spring arm for moving the converter ball up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding cam in the upper surface of the output shaft.

19 Claims, 6 Drawing Figures PATENTEU 19 I972 3.693.124

INVENT OR. RAYMOND J. GANOWSKY ATTORNEYS ROTARY STEPPING SOLENOID BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to rotary solenoids and more particularly to a rotary stepping solenoid of the hinged armature type.

Description of the Prior Art Rotary stepping solenoids are known wherein the output shaft has the capability of rotating through an arc upon the application of electrical energy to the solenoid coil. Upon de-energization of the coil, the output shaft is mechanically detented so that it stays in the last position to which it was powered. The energization cycle can then be repeated causing the output shaft to again rotate through an arc. The output shaft can therefore be made to rotate through a predetermined are, for example, 360 degrees, in discreet steps.

Known rotary stepping solenoids are subject to various disadvantages including their reliance upon clutches and ratchets to achieve their stepping action.

It is an object of the present invention to provide a rotary stepping solenoid that: is compact in size, low in cost, has a high operating speed, has long life, is of simple design, has an armature balanced against vibration and shock, has a shaft which is free-wheeling (i.e. can be rotated in any direction mechanically by the output shaft), has an automatic anti-overcoast feature (i.e. overcoast is when the output shaft has a tendency to travel further than desired due to lack of restraint), and has low inertia.

It is another object of the present invention to provide a rotary stepping solenoid method and apparatus for the direct conversion of a plurality or series of arcuate movements of a hinged armature into incremental unidirectional movement of the output shaft (the term direct is herein defined for use in the present specification and claims as being without the intermediary of a separate auxiliary ratchet mechanism, and of a scroll return spring for providing arcuate back and forth movement of one of the two cam members).

SUMMARY OF THE INVENTION A rotary stepping solenoid of the hinged armature type including a solenoid housing, a solenoid coil winding in the housing, an output shaft rotatably mounted in the coil winding, an armature hingedly connected to the housing, and converter means between the annature and shaft for converting arcuate movement of the armature into rotary movement of the shaft. The converter means comprises a single ball, a single cam in a lower surface of the armature, and a plurality of ball race cams equally spaced around the periphery of the upper surface of the shaft. The rotary stepping solenoid also includes detent means for holding the shaft in the position to which it is moved, means for spring-biasing the armature to its upper de-energized position off of the housing, and a spring arm for urging the ball up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding cam in the upper surface of the output shaft, whereby upon subsequent energization of the solenoid, the converter means will cause said output shaft to rotate an additional discreet step.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood by reference to the following detailed description thereof, when read in conjunction with the attached drawings, wherein like reference numerals refer to like elements, and wherein:

FIG. 1 is a vertical, partial cross-sectional view through a rotary stepping solenoid according to the present invention;

FIG. 2 is a top view along line 2-2 of FIG. 1 showing the spring arm of the present invention for urging the ball into the next succeeding ball race cam in the upper surface of the output shaft;

FIG. 3 is a diagrammatic view showing the operation of the spring arm of FIG. 2; and

FIGS. 4-6 are each a top view of the upper surface of an output shaft having a four position stepper cam, an eight position stepper cam, and a two position stepper cam, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now'to the drawings, FIG. 1 shows a rotary stepping solenoid l0 constructed in accordance with the present invention. The solenoid 10 of the present invention is similar to the rotary solenoids described in U.S. Pat. application Ser. No. 93,157 entitled Improvement in Rotary Solenoid, filed Nov. 27, I970, by applicant, and in U.S. Pat. No. 3,419,831.

The rotary stepping solenoid 10 comprises generally a machined or formed solenoid housing 12 provided with an annular groove 14 in a top surface 16 thereof. A suitable annular solenoid coil winding 18 at least partly encapsulated in an epoxy resin layer 20 is positioned in the groove 14. A rotary output shaft 22 is rotatably mounted, by suitable bearing means, within a central cylindrical opening 24 of the casing 12. An armature 26 is hingedly connected to the top surface 16 of the housing 12 by means of a flexible hinge 28. A dust cover 30 is connected to the housing 12 and encloses the armature 26. The armature 26 includes an opening 32 through which an adjustable limit screw or post 34 extends, for limiting the upward movement of the armature 26.

The rotary stepping solenoid 10 includes a converter means 36, including a single ball 38 positioned between a pair of oppositely inclining converter ball race cams 40 and 42 in a lower surface 43 of the armature 26 and in an upper surface 45 of the output shaft 22, respectively. The converter means 36 converts downward arcuate movement of the armature 26, responsive to the magnetic field of the coil winding 18 when energized, into a predetermined discreet amount of rotary movement of the output shaft 22.

According to the present invention, means are provided for upwardly biasing the armature 26 to its upper, de-energized position, such that the armature 26 will always be in its upper position whenever the coil winding 18 is not energized. In the preferred embodiment, this is achieved by means of the hinge 28 being a flexible metal spring hinge having an upwardly directed set or bias, provided, for example, by properly bending the flexible spring hinge 28. Other means can be used, such as additional spring means located in various positions,

to provide the upward bias to the armature 26, as will be clearly understood by one skilled in the art.

It is to be noted that the stepping solenoid of the present invention does not include a torsion return spring adjacent the bottom of the housing 12 and contacting the output shaft 22 for biasing the shaft rotatably toward its de-energized position. The sole noid 10 does, however, include a detent assembly 44 connected to the bottom of the housing 12. The detent assembly 44 can be any of the known types of detent assemblies, and therefore need not be described in detail herein. The specific construction and operation of the detent assembly forms no part of the present invention. The detent assembly 44 can include, for example, a detent wheel 46, a detent ball 48 and a detent spring 50. The detent wheel 46 is connected to the output shaft 22, and upon energization of the solenoid 10, the output shaft 22 is rotated a predetermined discreet amount, to a moved position in which the detent wheel 46 and the shaft 22 are held by the detent ball 48 and the detent spring 50.

The rotary stepping solenoid l includes-a single ball cam race 40 in the armature 26, and a plurality of ball cam races 42 in the upper surface 45 of the output shaft 22. FIG. 4 is a top view of the output shaft 22 having four identical cams 42, 42A, 42B, and 42C equally spaced around the periphery of the upper surface 45 of the shaft 22. This provides a four-position stepper, and it will be evident to one skilled in the art that other numbers of cams can be employed such as, for example, an eight-position stepper cam 65 shown in FIG. 5, and a two position stepper cam 67 shown in FIG. 6.

Referring now to FIGS. 2 and 3, the rotary stepping solenoid includes means for urging the ball 38 up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding cam 42A in the output shaft 22, after deenergization of the solenoid 10. This urging means comprises preferably a spring arm 54 connected at one end 55 thereof to an annular portion 56 of the housing 12. The other end 57 of the spring arm 54 is biased into contact with the ball 38 and exerts a force on the ball 38 in the direction opposite to the direction of rotation of the output shaft 22. FIG. 2 shows the end 55 of the spring arm 54 connected (by a screw not shown) to the central annular portion 56 of the housing 12 in a notch or groove 58 therein. The spring arm 54 extends across the upper surface 45 of the output shaft 22 and terminates in the freely moving end 57 thereof, located in a groove 60 in an opposite side of the annular portion 56.

The operation of the spring 54 will be more readily understood by reference to FIG. 3 showing the position of the spring arm 54, the ball 38, the ball cam race 40 of the armature 26, and the ball cam race 42 of the output shaft 22. The various elements are shown by solid lines in their energized position, and by dotted lines in their de-energized position. As will be seen in FIG. 3, when the solenoid 10 is energized, the armature 26 moves downwardly to its energized position and the ball 38 moves as far as possible to the left as shown in FIG. 3, and the output shaft 22 moves to the right as shown in FIG. 3. The energization force of the solenoid l0 overcomes the smaller force of the spring arm 54. However, upon de-energization of the solenoid 10, the

armature 26 is caused to move upwardly to its de-energized position by means of the spring bias of its hinge 28, and at the same time the spring bias of the spring arm 54 forces the ball 38 to the right (as viewed in FIG. 3) to the dotted line position. The spring arm 54 forces the ball 38 up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding ball race cam 42A in the shaft 22, adjacent the previously employed ball race cam 42. In the de-energized condition of the solenoid 10, the ball 38 is out of contact with the shallow ends of the cams 40 and 42, which will allow the output shaft 22 to be free-wheeling, and in the energized condition, the ball is in contact with the deep end of the cams.

The energization of the solenoid 10 can be repeated over and over again, and each time the solenoid 10 is energized, the output shaft 22 is caused to rotate a discreet amount depending, for example, upon the number of cams in the ball race cam 42 in the upper surface 45 of the output shaft 22. The operation of the ball 38 in causing the output shaft 22 to rotate as it rolls between the oppositely inclined ball race cams in the armature and the output shaft is the same as in the known rotary solenoids of the hinged armature type referred to above. The primary difference in the present invention is that the output shaft is provided with a plurality of cams equally spaced around the periphery of the upper surface of the shaft, the armature is spring loaded upwardly, the converter ball is forced by a spring arm into operative position with respect to the next succeeding output shaft cam, the torsion return spring is eliminated and a detent assembly is added.

It is to be understood that the various modifications and changes from the above described preferred embodiment can be made as will be recognized by one skilled in the art, for example, different spring means for upwardly biasing the armature can be used, different means for forcing the ball into operative position with respect to the next succeeding ball race cam of the output shaft can be used, other detent means can be used, and various types and sizes and numbers of ball race cams can be used in the upper surface of the output shaft.

The invention has been described in detail with particular reference to the preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as defined in the appended claims.

lclairn:

1. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a predetermined discreet amount of rotational movement of said shaft, the improvement comprising:

a. detent means for holding said output shaft in its moved position, and

b. said converter means including means for converting a subsequent arcuate movement of said armature to an additional predetermined discreet amount of rotational movement of said shaft.

2. The apparatus according to claim 1 wherein said converter means includes ball means, a ball race cam in a lower surface of said armature and a plurality of ball race cams in an upper surface of said output shaft adjacent said lower surface of said armature, and wherein said armature has an upper de-energized position and a lower energized position.

3. The apparatus according to claim 2 including means for returning said armature to its de-energized position when said coil winding is de-energized.

4. The apparatus according to claim 3 wherein said hinged armature is connected to said housing by a spring hinge and wherein said returning means is said spring hinge having an upwardly directed bias.

5. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a pre-determined discreet amount of rotational movement of said shaft, the improvement comprising:

a. detent means for holding said output shaft in its moved position,

b. said converter means including means for converting a subsequent arcuate movement of said armature to an additional predetermined discreet amount of rotational movement of said shaft,

c. said converter means including ball means, a ball race cam in a lower surface of said armature and a plurality of ball race cams in an upper surface of said output shaft adjacent said lower surface of said armature, and wherein said armature has an upper de-energized position and a lower energized position,

d. means for returning said armature to its deenergized position when said coil winding is de-energized, and

e. means for forcing said ball means into operative position with respect to the next succeeding cam of said output shaft.

6. The apparatus according to claim 5 wherein said forcing means comprises a spring arm biased into contact with said ball means for urging said ball means up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding cam of said output shaft.

7. The apparatus according to claim 6 wherein said ball, said ball race cam in said armature and said ball race cams in said output shaft are so proportioned in shape and size that upon de-energization of said solenoid, said spring arm forces said ball means to the shallow end of said ball race cam in said armature, in which position the ball means is located in operative position with respect to the shallow end of said next succeeding cam of said output shaft.

8. The apparatus according to claim 7 wherein said spring arm has a substantially circular cross-section.

9. The apparatus according to claim 7 wherein said ball means comprises only a single ball.

10. The apparatus according to claim 9 wherein said plurality of ball race cams comprises two identical ball race cams equally spaced peripherally around said upper surface of said output shaft.

11. The apparatus according to claim 9 wherein said plurality of ball race cams comprises four identical ball race cams equally spaced peripherally around said upper surface of said output shaft.

12. The apparatus according to claim 9 wherein said plurality of ball race cams comprises eight identical ball race cams equally spaced peripherally around said upper surface of said output shaft.

13. The apparatus according to claim 2 wherein said ball means comprises only a single ball.

14. A arcuate stepping solenoid comprising:

a. a rotary solenoid of the hinged armature type wherein arcuate movement of a hinged armature is converted to rotary movement of an output shaft through a converter means,

b. detent means for holding said output shaft in its moved position, and

c. said converter means including means for converting a subsequent arcuate movement of said armature to an additional predetermined discreet amount of rotational movement of said shaft.

15. The apparatus according to claim 14 wherein said converter means comprises a single ball, a single ball race cam on a lower surface of said armature and a plurality of identical ball race cams equally spaced around the periphery of an upper surface of said output shaft in operative association with said ball race cam of said armature.

16. The apparatus according to claim 15 including means for forcing said ball means into operative position with respect to the next succeeding cam of said output shaft.

17. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a predetermined discreet amount of rotational movement of said shaft, the improvement comprising:

a. detent means for holding said output shaft in its moved position, and

b. said converter means including means for directly converting a series of arcuate movements of said armature into incremental unidirectional arcuate movement of said output shaft.

18. A method for producing rotary stepped motion of an output shaft of a rotary solenoid comprising:

a. providing a rotary solenoid of the hinged armature type wherein arcuate movement of the hinged armature is converted to arcuate movement of an output shaft through a converter means, and

b. directly converting a series of back and forth arcuate movements of said armature into incremental unidirectional arcuate movement of said output shaft.

forcing said ball into operative position with respect to the next succeeding cam of said output shaft following de-energization of said solenoid, whereby said output shaft is directly provided with incremental unidirectional arcuate movement in response to arcuate movement of said armature.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. g 6o3 gu Dated September 19, 1972 Inventor(s) Raymond J. Ganowsky It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1 line 1, before the word "stepping" delete "arcuate and substitute therefor --rotary-.

Claim 1 para rraph a. line 3, before the word "movement" delete "rotary and substitute therefor --arcuate--.

Signed and sealed. this 13th day of February 1973..

(SEAL) Attest:

EDWARD M.FLETCHER,JR. I ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents F ORM PO-105O (10-69) USCOMM-DC 60376-P69 a us, eovznmuzm PRINTING omc: ms 0-366-334 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. g 6o3 gh Dated September 19, 1972 Inventor(s) Raymond J. Ganowsky It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 14, line 1, before the word "stepping""delete "arouate and substitute therefor --rotary--. i

Claim 14, para raph a. line 3, before the word "movement" delete "rotary and substitute therefor ----.arcuate----.

Signed and sealed this 13th day of February 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents FORM PO-105O (10-69) USCQMM-DC 60a76-P69 w u.sl GOVERNMENT PRINTING OFFICE: less O366-334 

1. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a predetermined discreet amount of rotational movement of said shaft, the improvement comprising: a. detent means for holding said output shaft in its moved position, and b. said converter means including means for converting a subsequent arcuate movement of said armature to an additional predetermined discreet amount of rotational movement of said shaft.
 2. The apparatus according to claim 1 wherein said converter means includes ball means, a ball race cam in a lower surface of said armature and a plurality of ball race cams in an upper surface of said output shaft adjacent said lower surface of said armature, and wherein said armature has an upper de-energized position and a lower energized position.
 3. The apparatus according to claim 2 including means for returning said armature to its de-energized position when said coil winding is de-energized.
 4. The apparatus according to claim 3 wherein said hinged armature is connected to said housing by a spring hinge and wherein said returning means is said spring hinge having an upwardly directed bias.
 5. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a pre-determined discreet amount of rotational movement of said shaft, the improvement comprising: a. detent means for holding said output shaft in its moved position, b. said converter means including means for converting a subsequent arcuate movement of said armature to an additionaL predetermined discreet amount of rotational movement of said shaft, c. said converter means including ball means, a ball race cam in a lower surface of said armature and a plurality of ball race cams in an upper surface of said output shaft adjacent said lower surface of said armature, and wherein said armature has an upper de-energized position and a lower energized position, d. means for returning said armature to its deenergized position when said coil winding is de-energized, and e. means for forcing said ball means into operative position with respect to the next succeeding cam of said output shaft.
 6. The apparatus according to claim 5 wherein said forcing means comprises a spring arm biased into contact with said ball means for urging said ball means up into the armature cam and out of contact with the shaft cam but in operative position with respect to the next succeeding cam of said output shaft.
 7. The apparatus according to claim 6 wherein said ball, said ball race cam in said armature and said ball race cams in said output shaft are so proportioned in shape and size that upon de-energization of said solenoid, said spring arm forces said ball means to the shallow end of said ball race cam in said armature, in which position the ball means is located in operative position with respect to the shallow end of said next succeeding cam of said output shaft.
 8. The apparatus according to claim 7 wherein said spring arm has a substantially circular cross-section.
 9. The apparatus according to claim 7 wherein said ball means comprises only a single ball.
 10. The apparatus according to claim 9 wherein said plurality of ball race cams comprises two identical ball race cams equally spaced peripherally around said upper surface of said output shaft.
 11. The apparatus according to claim 9 wherein said plurality of ball race cams comprises four identical ball race cams equally spaced peripherally around said upper surface of said output shaft.
 12. The apparatus according to claim 9 wherein said plurality of ball race cams comprises eight identical ball race cams equally spaced peripherally around said upper surface of said output shaft.
 13. The apparatus according to claim 2 wherein said ball means comprises only a single ball.
 14. A arcuate stepping solenoid comprising: a. a rotary solenoid of the hinged armature type wherein arcuate movement of a hinged armature is converted to rotary movement of an output shaft through a converter means, b. detent means for holding said output shaft in its moved position, and c. said converter means including means for converting a subsequent arcuate movement of said armature to an additional predetermined discreet amount of rotational movement of said shaft.
 15. The apparatus according to claim 14 wherein said converter means comprises a single ball, a single ball race cam on a lower surface of said armature and a plurality of identical ball race cams equally spaced around the periphery of an upper surface of said output shaft in operative association with said ball race cam of said armature.
 16. The apparatus according to claim 15 including means for forcing said ball means into operative position with respect to the next succeeding cam of said output shaft.
 17. In a rotary solenoid of the hinged armature type including a solenoid housing, an annular solenoid coil winding in said housing, an output shaft mounted for rotary movement within said coil winding, an armature hingedly connected to said housing for arcuate movement relative to said output shaft responsive to the magnetic field of said coil winding, and converter means between said armature and said output shaft for converting arcuate movement of said armature to a predetermined discreet amount of rotational movement of said shaft, the improvement comprising: a. detent means for holding said output shaft in its moved position, and b. said converter means including means for directly converting a series of arcuate movemeNts of said armature into incremental unidirectional arcuate movement of said output shaft.
 18. A method for producing rotary stepped motion of an output shaft of a rotary solenoid comprising: a. providing a rotary solenoid of the hinged armature type wherein arcuate movement of the hinged armature is converted to arcuate movement of an output shaft through a converter means, and b. directly converting a series of back and forth arcuate movements of said armature into incremental unidirectional arcuate movement of said output shaft.
 19. The method according to claim 18 wherein said directly converting step comprises providing said output shaft with a plurality of ball race cams spaced around the periphery of an upper surface of said output shaft in operative association with a ball race cam in a lower surface of said armature and with a ball between said cams and holding said output shaft in its moved position after every arcuate movement thereof, and forcing said ball into operative position with respect to the next succeeding cam of said output shaft following de-energization of said solenoid, whereby said output shaft is directly provided with incremental unidirectional arcuate movement in response to arcuate movement of said armature. 